function ShowCustomerInf( ) {
    var cookies = document.cookie;
    var list = cookies.split("; ");          // 解析出名/值对列表
    for(var i = 0; i < list.length; i++) {
        var arr = list[i].split("=");          // 解析出名和值
        if(arr[0]==='username'){
            console.log(decodeURIComponent(arr[1])) ;   // 对cookie值解码
            document.getElementById("login").innerText=decodeURIComponent(arr[1])+'已登录';
            document.getElementById("exit").style='block';
        }
    }
}
